Ultra-wide-angle optical imaging lens

Abstract

The present invention relates to the field of lens technology. The present invention discloses an ultra-wide-angle optical imaging lens, comprising nine lenses, wherein the first and second lenses are convex-concave lenses with negative refractive power, the third lens is a plano-concave lens with negative refractive power, the fourth lens is a concave-convex lens with negative refractive power, the fifth lens, the sixth lens, and the eighth lens are all convex-convex lenses with positive refractive power, the seventh lens is a concave-concave lens with negative refractive power, the ninth lens has a negative refractive power and the object side surface is convex near the optical axis and the image side surface is concave near the optical axis, the object side surfaces and the image side surfaces of the fourth to ninth lenses are all aspherical surfaces, the first to third lenses are all glass lenses, and the fourth, sixth, seventh, eighth, and ninth lenses are all plastic lenses. The present invention has the advantages of a large field of view, high high-frequency resolution, good imaging quality, and good temperature drift control.

Description

Technical Field

[0001] The present invention belongs to the technical field of lenses, and in particular relates to an ultra-wide-angle optical imaging lens for video scenes. Background Art

[0002] With the continuous advancement of science and technology and the continuous improvement of living standards, optical imaging lenses have also developed rapidly in recent years. Optical imaging lenses are widely used in various fields such as smartphones, tablets, vehicle-mounted monitoring, security monitoring, drone aerial photography, machine vision systems, video conferencing, etc.

[0003] The technical requirements for optical imaging lenses used in video conferencing are constantly increasing. These lenses are required to provide sharp, clear low-frequency resolution for viewing localized objects, while also maintaining high-frequency resolution for clear overall imagery. Currently, the high-frequency resolution of existing optical imaging lenses used in video conferencing is insufficient and requires further improvement. Summary of the Invention

[0004] The object of the present invention is to provide an ultra-wide-angle optical imaging lens to solve the above-mentioned technical problems.

[0005] To achieve the above objectives, the present invention adopts a technical solution: an ultra-wide-angle optical imaging lens, comprising, in order from the object side to the image side along an optical axis, first to ninth lenses; each of the first to ninth lenses includes an object-side surface facing the object side and through which imaging light passes, and an image-side surface facing the image side and through which imaging light passes;

[0006] The first lens has negative refractive power, the object-side surface of the first lens is convex, and the image-side surface of the first lens is concave;

[0007] The second lens has negative refractive power, the object-side surface of the second lens is convex, and the image-side surface of the second lens is concave;

[0008] The third lens has a negative refractive power, the object side surface of the third lens is a flat surface, and the image side surface of the third lens is a concave surface;

[0009] The fourth lens element has negative refractive power, the object-side surface of the fourth lens element is concave, and the image-side surface of the fourth lens element is convex;

[0010] The fifth lens element has positive refractive power, the object-side surface of the fifth lens element is convex, and the image-side surface of the fifth lens element is convex;

[0011] The sixth lens element has positive refractive power, the object-side surface of the sixth lens element is convex, and the image-side surface of the sixth lens element is convex;

[0012] The seventh lens element has negative refractive power, the object-side surface of the seventh lens element is concave, and the image-side surface of the seventh lens element is concave;

[0013] The eighth lens has a positive diopter, the object side of the eighth lens is convex, and the image side of the eighth lens is convex;

[0014] The ninth lens has a negative diopter, the object side of the ninth lens is convex near the optical axis, and the image side of the ninth lens is concave near the optical axis;

[0015] The object sides and image sides of the fourth to ninth lenses are aspherical surfaces, the first to third lenses are all glass lenses, and the fourth, sixth, seventh, eighth, and ninth lenses are all plastic lenses;

[0016] The only lenses with refractive power in this ultra-wide-angle optical imaging lens are the first to ninth lenses described above.

[0017] Furthermore, the fifth lens is a glass lens.

[0018] Furthermore, this ultra-wide-angle optical imaging lens also satisfies: 1.70 < nd1 < 1.90, 35.00 < vd1 < 55.00; 1.70 < nd2 < 1.90, 35.00 < vd2 < 55.00; 1.50 < nd3 < 1.70, 55.00 < vd3 < 70.00, where nd1 - nd3 are the refractive indices of the first to third lenses respectively, and vd1 - vd3 are the dispersion coefficients of the first to third lenses respectively.

[0019] Even further, this ultra-wide-angle optical imaging lens also satisfies: nd2 > 1.80, where nd2 is the refractive index of the second lens.

[0020] Furthermore, this ultra-wide-angle optical imaging lens also satisfies: 1.50 < nd4 < 1.70, 20.00 < vd4 < 30.00; 1.50 < nd5 < 1.70, 55.00 < vd5 < 70.00; 1.50 < nd6 < 1.60, 50.00 < vd6 < 70.00; 1.50 < nd7 < 1.70, 20.00 < vd7 < 30.00; 1.50 < nd8 < 1.60, 50.00 < vd8 < 70.00; 1.50 < nd9 < 1.70, 19.00 < vd9 < 30.00, where nd4 - nd9 are the refractive indices of the fourth to ninth lenses respectively, and vd4 - vd9 are the dispersion coefficients of the fourth to ninth lenses respectively.

[0021] Furthermore, it also includes an aperture, and the aperture is arranged between the fifth lens and the sixth lens.

[0022] Further, the ultra-wide-angle optical imaging lens further satisfies: 45.0 < TTL / f < 49.0, where TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, and f is the focal length of the ultra-wide-angle optical imaging lens.

[0023] Further, the object side and the image side of the fourth lens to the ninth lens are both high-order even aspherical surfaces.

[0024] Further, the ultra-wide-angle optical imaging lens further satisfies: TTL < 55.0 mm, where TTL is the distance from the object side of the first lens to the imaging surface on the optical axis. <00​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ Figure 8 This is a magnification chromatic aberration curve of visible light at 555 nm according to Example 2 of the present invention;

[0036] Figure 9 This is a structural diagram of embodiment 3 of the present invention;

[0037] Figure 10 This is the MTF diagram of Example 3 of the present invention under visible light 435-650nm;

[0038] Figure 11 This is a graph showing the field curvature and distortion curves of Example 3 of the present invention under visible light of 435nm-650nm;

[0039] Figure 12 This is a magnification chromatic aberration curve of visible light 555nm according to Example 3 of the present invention. DETAILED DESCRIPTION

[0040] To further illustrate various embodiments, the present invention is provided with accompanying drawings. These drawings form part of the present disclosure and are primarily used to illustrate the embodiments and, in conjunction with the relevant description in the specification, to explain the operating principles of the embodiments. By referring to these drawings, one of ordinary skill in the art will understand other possible embodiments and the advantages of the present invention. The components in the figures are not drawn to scale, and similar reference numerals are generally used to represent similar components.

[0041] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0042] "A lens having a positive (or negative) refractive power" means that the lens's paraxial refractive power, calculated using Gaussian optics theory, is positive (or negative). The "object-side (or image-side) of a lens" is defined as the specific area of ​​the lens surface through which the imaging light passes. The concavity or convexity of a lens's surface can be determined using the same method commonly used by those skilled in the art: the sign of the radius of curvature (abbreviated as R value) determines the concavity or convexity of the lens's surface. R values ​​are commonly used in optical design software such as Zemax or CodeV. R values ​​are also commonly found in lens data sheets within optical design software. For the object-side surface, a positive R value indicates a convex surface; a negative R value indicates a concave surface. Conversely, for the image-side surface, a positive R value indicates a concave surface; a negative R value indicates a convex surface.

[0043] The present invention discloses an ultra-wide-angle optical imaging lens, which includes, in sequence from the object side to the image side along an optical axis, first to ninth lenses; each of the first to ninth lenses includes an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing imaging light to pass through.

[0044] The first lens has negative refractive power, the object-side surface of the first lens is convex, and the image-side surface of the first lens is concave.

[0045] The second lens has negative refractive power, the object-side surface of the second lens is convex, and the image-side surface of the second lens is concave.

[0046] The third lens element has negative refractive power, the object-side surface of the third lens element is a flat surface, and the image-side surface of the third lens element is a concave surface.

[0047] The fourth lens element has negative refractive power, the object-side surface of the fourth lens element is concave, and the image-side surface of the fourth lens element is convex.

[0048] The fifth lens element has positive refractive power, the object-side surface of the fifth lens element is convex, and the image-side surface of the fifth lens element is convex.

[0049] The sixth lens element has positive refractive power, an object-side surface of the sixth lens element is convex, and an image-side surface of the sixth lens element is convex.

[0050] The seventh lens element has negative refractive power, the object-side surface of the seventh lens element is concave, and the image-side surface of the seventh lens element is concave.

[0051] The eighth lens element has positive refractive power, the object-side surface of the eighth lens element is convex, and the image-side surface of the eighth lens element is convex.

[0052] The ninth lens element has negative refractive power, the object-side surface of the ninth lens element is convex near the optical axis, and the image-side surface of the ninth lens element is concave near the optical axis.

[0053] The object-side surfaces and image-side surfaces of the fourth to ninth lenses are all aspherical, which effectively suppresses spherical aberration, chromatic aberration, field curvature and astigmatism of the optical system.

[0054] The first to third lenses are all glass lenses, and the fourth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all plastic lenses.

[0055] The ultra-wide-angle optical imaging lens has only the first to ninth lenses mentioned above as lenses with refractive powers.

[0056] The present invention adopts nine lenses, glass-plastic hybrid design, and through the corresponding design of each lens, it has the advantages of large field of view, high high-frequency resolution, good imaging quality, good temperature drift control, and small image quality changes under different working environments.

[0057] Preferably, the fifth lens is a glass lens, which further improves the resolution of the optical system and suppresses temperature drift.

[0058] Preferably, the ultra-wide-angle optical imaging lens further satisfies: 1.70 < nd1 < 1.90, 35.00 < vd1 < 55.00; 1.70 < nd2 < 1.90, 35.00 < vd2 < 55.00; 1.50 < nd3 < 1.70, 55.00 < vd3 < 70.00, where nd1-nd3 are the refractive indices of the first lens to the third lens respectively, and vd1-vd3 are the dispersion coefficients of the first lens to the third lens respectively. By continuously using three negative refractive power lenses and using high refractive index materials, the aberration of the outer field of view can be optimized, the light beam can be expanded, so that the deflection angle of the light on each lens gradually increases, the sensitivity of the lens decreases, and at the same time, the outer diameter of the subsequent lens is effectively reduced, taking into account both a large field of view angle and a small volume.

[0059] More preferably, the ultra-wide-angle optical imaging lens further satisfies: nd2 > 1.80, where nd2 is the refractive index of the second lens. By using a lens with a high refractive index material, the distance between the lenses can be reduced, and the total length of the optical system can be effectively shortened.

[0060] Preferably, the ultra-wide-angle optical imaging lens further satisfies: 1.50 < nd4 < 1.70, 20.00 < vd4 < 30.00; 1.50 < nd5 < 1.70, 55.00 < vd5 < 70.00; 1.50 < nd6 < 1.60, 50.00 < vd6 < 70.00; 1.50 < nd7 < 1.70, 20.00 < vd7 < 30.00; 1.50 < nd8 < 1.60, 50.00 < vd8 < 70.00; 1.50 < nd9 < 1.70, 19.00 < vd9 < 30.00, where nd4-nd9 are the refractive indices of the fourth lens to the ninth lens respectively, and vd4-vd9 are the dispersion coefficients of the fourth lens to the ninth lens respectively. Further optimize chromatic aberration and aberration, and improve the imaging quality.

[0061] Preferably, it further includes an aperture, and the aperture is arranged between the fifth lens and the sixth lens, which can correct astigmatism, and in particular can well correct coma, distortion and lateral aberration. <{

[0062] Preferably, the ultra-wide-angle optical imaging lens further satisfies: 45.0 < TTL / f < 49.0, where TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, and f is the focal length of the ultra-wide-angle optical imaging lens, to avoid the imaging quality being reduced due to the ultra-wide-angle optical imaging lens being too small in volume, or being unfavorable for the miniaturization of the lens due to the ultra-wide-angle optical imaging lens being too large in volume.

[0063] Preferably, the object side surface and the image side surface of the fourth lens to the ninth lens are both high-order even aspherical surfaces, which can reduce the number of lenses used, effectively reduce the volume of the lens, and at the same time effectively control the edge distortion.

[0064] Preferably, the ultra-wide-angle optical imaging lens further satisfies: TTL<55.0 mm, where TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, effectively reducing the size of the lens.

[0065] The ultra-wide-angle optical imaging lens of the present invention will be described in detail below with reference to specific embodiments.

[0066] Example 1

[0067] like Figure 1 As shown, an ultra-wide-angle optical imaging lens comprises, in order from object side A1 to image side A2 along optical axis I, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, an aperture 100, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a protective glass 110, and an imaging surface 120. The first lens 1 to the ninth lens 9 each include an object-side surface facing the object side A1 and through which imaging light passes, and an image-side surface facing the image side A2 and through which imaging light passes.

[0068] The first lens element 1 has negative refractive power. The object-side surface 11 of the first lens element 1 is convex, and the image-side surface 12 of the first lens element 1 is concave.

[0069] The second lens element 2 has negative refractive power. The object-side surface 21 of the second lens element 2 is convex, and the image-side surface 22 of the second lens element 2 is concave.

[0070] The third lens element 3 has negative refractive power. The object-side surface 31 of the third lens element 3 is a flat surface, and the image-side surface 32 of the third lens element 3 is a concave surface.

[0071] The fourth lens element 4 has negative refractive power. The object-side surface 41 of the fourth lens element 4 is concave, and the image-side surface 42 of the fourth lens element 4 is convex.

[0072] The fifth lens element 5 has positive refractive power. The object-side surface 51 of the fifth lens element 5 is convex, and the image-side surface 52 of the fifth lens element 5 is convex.

[0073] The sixth lens element 6 has positive refractive power. The object-side surface 61 of the sixth lens element 6 is convex, and the image-side surface 62 of the sixth lens element 6 is convex.

[0074] The seventh lens element 7 has negative refractive power. The object-side surface 71 of the seventh lens element 7 is concave, and the image-side surface 72 of the seventh lens element 7 is concave.

[0075] The eighth lens element 8 has positive refractive power. The object-side surface 81 of the eighth lens element 8 is convex, and the image-side surface 82 of the eighth lens element 8 is convex.

[0076] The ninth lens element 9 has negative refractive power. The object-side surface 91 of the ninth lens element 9 is convex near the optical axis, and the image-side surface 92 of the ninth lens element 9 is concave near the optical axis.

[0077] The first lens 1 to the third lens 3 are all glass spherical lenses.

[0078] The fifth lens 5 is a glass aspherical lens, but is not limited thereto. In some embodiments, the fifth lens 5 may also be made of other optical materials.

[0079] The fourth lens 4 , the sixth lens 6 , the seventh lens 7 , and the eighth lens 8 to the ninth lens 9 are all plastic aspherical lenses.

[0080] In this specific embodiment, the aperture 100 is disposed between the fifth lens 5 and the sixth lens 6 , but is not limited thereto. In other embodiments, the aperture 100 may also be disposed at other appropriate positions.

[0081] In some embodiments, the protective glass 110 may also be replaced by a filter.

[0082] The detailed optical data of this specific embodiment are shown in Table 1-1.

[0083] Table 1-1 Detailed optical data of Example 1

[0084] surface Diameter / mm Curvature radius / mm Thickness / interval / mm Material Refractive index Dispersion coefficient Focal length / mm - Infinity Infinity 11 First lens 48.024 33.832 2.795 H-ZLAF52A 1.81 41.02 -41.208 12 29.769 16.178 5.793 21 Second lens 28.538 26.550 1.550 H-ZLAF50E 1.81 46.57 -20.836 22 18.350 10.027 6.096 31 The third lens 18.093 Infinity 1.000 H-LAK4L 1.64 60.21 -13.628 32 13.674 8.749 6.917 41 Fourth lens 13.427 -7.684 6.674 EP6000 1.64 23.53 -80.446 42 16.492 -12.091 1.918 51 Fifth lens 17.810 29.610 8.402 D-ZK3 1.59 61.28 12.673 52 17.324 -8.952 7.852 100 aperture 1.805 Infinity 0.048 61 Sixth lens 1.972 3.226 1.145 T62R 1.54 55.98 3.740 62 2.236 -4.689 0.113 71 Seventh lens 2.268 -3.569 0.534 EP6000 1.64 23.53 -3.137 72 2.520 4.930 0.195 81 Eighth lens 3.417 3.308 1.495 T62R 1.54 55.98 6.063 82 3.756 -204.939 0.164 91 Ninth lens 3.769 5.118 0.999 EP9000 1.68 19.28 118.745 92 4.503 5.036 0.400 110 Protective glass 4.846 Infinity 0.210 H-K9L 1.52 64.20 Infinity - 4.959 Infinity 0.536 120 Imaging surface 5.459 Infinity 0.000

[0085] In this specific embodiment, the object side surface 41, the object side surface 51, the object side surface 61, the object side surface 71, the object side surface 81, the object side surface 91, the image side surface 42, the image side surface 52, the image side surface 62, the image side surface 72, the image side surface 82, and the image side surface 92 are defined according to the following aspheric curve formula:

[0086]

[0087] in:

[0088] r is the distance from a point on the optical surface to the optical axis.

[0089] z is the sagittal height of the point along the optical axis.

[0090] c is the curvature of the surface.

[0091] K is the quadratic constant of the surface.

[0092] A4、A6、A8、A 10 、A 12 、A 14 、A 16 They are: fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order aspheric coefficients.

[0093] Please refer to the table below for detailed parameter data of each aspheric surface:

[0094]

[0095] Please refer to Table 4 for the values ​​of the relevant conditional expressions of this specific embodiment.

[0096] The MTF curve of this specific embodiment is shown in Figure 2 , it can be seen that the full-field MTF at 280lp / mm is greater than 0.3, the high-frequency resolution is high, and the image quality is good (because this ultra-wide-angle optical imaging lens focuses on the image quality within the 110°-210° field of view, there is no central field of view and the central field of view is not in focus); for details of the field curvature and distortion diagram, see Figure 3 (A) and (B) show that the field curvature curves of each wavelength coincide, and the lens chromatic aberration is well corrected; the distortion is <25%, and the image will not be affected by excessive distortion. For details of the magnification chromatic aberration diagram, see Figure 4 , it can be seen that the lens magnification chromatic aberration is less than 4μm.

[0097] In this specific embodiment, the focal length of the optical imaging lens is f=1.19 mm; the aperture value FNO=2.35; the field of view angle FOV=210.0°; and the distance TTL from the object-side surface 11 of the first lens 1 to the imaging surface 120 on the optical axis I is 54.833 mm.

[0098] In this embodiment, the image quality changes slightly under different operating temperature environments.

[0099] Example 2

[0100] like Figure 5 As shown, the surface profiles and refractive powers of the lenses of this embodiment and the first embodiment are substantially the same, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0101] The detailed optical data of this specific embodiment are shown in Table 2-1.

[0102] Table 2-1 Detailed optical data of Example 2

[0103] surface Diameter / mm Curvature radius / mm Thickness / interval / mm Material Refractive index Dispersion coefficient Focal length / mm - Infinity Infinity 11 First lens 47.5017 33.174 2.276 H-ZLAF52A 1.810 41.017 -43.912 12 30.6130 16.635 5.910 21 Second lens 29.2597 26.887 1.569 H-ZLAF50E 1.807 46.575 -21.978 22 18.9534 10.410 6.217 31 The third lens 18.6801 Infinity 1.914 H-LAK4L 1.642 60.214 -13.097 32 13.2345 8.408 6.229 41 Fourth lens 13.1580 -7.681 6.788 EP6000 1.644 23.529 -70.487 42 16.2079 -12.446 2.667 51 Fifth lens 17.6746 29.817 8.404 M-BACD5N 1.591 61.251 11.631 52 17.2907 -7.997 7.072 100 aperture 1.8720 Infinity 0.046 61 Sixth lens 2.0892 3.924 1.239 K26R 1.537 55.711 3.911 62 2.4326 -4.018 0.086 71 Seventh lens 2.4543 -3.619 0.619 EP6000 1.644 23.529 -3.197 72 2.8491 5.094 0.118 81 Eighth lens 3.7116 3.518 1.529 K26R 1.537 55.711 5.629 82 3.9159 -18.170 0.121 91 Ninth lens 3.9087 4.982 1.000 EP8000 1.667 20.382 -117.142 92 4.5680 4.307 0.686 110 Protective glass 5.1186 Infinity 0.21 H-K9L 1.518 64.199 Infinity - 5.2393 Infinity 0.266 120 Imaging surface 5.5020 Infinity 0

[0104] Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

[0105]

[0106] Please refer to Table 4 for the values ​​of the relevant conditional expressions of this specific embodiment.

[0107] The MTF curve of this specific embodiment is shown in Figure 6 It can be seen that the full field MTF at 280lp / mm is greater than 0.3, the high-frequency resolution is high, and the imaging quality is good; for details of the field curvature and distortion diagram, see Figure 7(A) and (B) show that the field curvature curves of each wavelength coincide, and the lens chromatic aberration is well corrected; the distortion is <27%, and the image will not be affected by excessive distortion. For details of the magnification chromatic aberration diagram, see Figure 8 , it can be seen that the lens magnification chromatic aberration is less than 4μm.

[0108] In this specific embodiment, the focal length of the optical imaging lens is f=1.17 mm; the aperture value FNO=2.17; the field of view angle FOV=210.0°; and the distance TTL from the object-side surface 11 of the first lens 1 to the imaging surface 120 on the optical axis I is 54.965 mm.

[0109] In this embodiment, the image quality changes slightly under different operating temperature environments.

[0110] Example 3

[0111] like Figure 9 As shown, the surface profiles and refractive powers of the lenses of this embodiment and the first embodiment are substantially the same, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0112] The detailed optical data of this specific embodiment are shown in Table 3-1.

[0113] Table 3-1 Detailed optical data of Example 3

[0114] surface Diameter / mm Curvature radius / mm Thickness / interval / mm Material Refractive index Dispersion coefficient Focal length / mm - Infinity Infinity 11 First lens 57.581 39.111 5.698 H-ZLAF52A 1.812 41.024 -42.383 12 31.497 17.107 5.917 21 Second lens 28.595 24.422 2.730 H-ZLAF50E 1.809 46.568 -19.616 22 16.726 9.137 5.939 31 The third lens 16.074 -88.014 1.152 H-LAK4L 1.643 60.214 -13.931 32 12.418 10.023 4.750 41 Fourth lens 12.198 -8.482 4.699 EP6000 1.647 23.529 -267.548 42 13.591 -10.860 3.772 51 Fifth lens 13.711 33.464 4.500 APL5015AL 1.547 56.003 12.682 52 13.527 -8.330 6.942 100 aperture 1.966 Infinity 0.0472 61 Sixth lens 2.373 2.741 1.011 K26R 1.538 55.634 3.451 62 2.595 -5.001 0.094 71 Seventh lens 2.576 -4.778 0.500 EP5000 1.642 23.972 -3.710 72 2.715 4.947 0.117 81 Eighth lens 2.854 3.315 0.999 K26R 1.538 55.634 8.459 82 3.195 10.934 0.626 91 Ninth lens 3.308 73.417 1.037 EP6000 1.647 23.529 119.740 92 4.576 1409.655 0.476 110 Protective glass 5.201 Infinity 0.21 H-K9L 1.519 64.212 Infinity - 5.297 Infinity 0.411 120 Imaging surface 5.496 Infinity 0

[0115] Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

[0116]

[0117] Please refer to Table 4 for the values ​​of the relevant conditional expressions of this specific embodiment.

[0118] The MTF curve of this specific embodiment is shown in Figure 10 It can be seen that the full field MTF at 280lp / mm is greater than 0.25, the high-frequency resolution is high, and the imaging quality is good; for details of the field curvature and distortion diagram, see Figure 11 (A) and (B) show that the field curvature curves of each wavelength coincide, and the lens chromatic aberration is well corrected; the distortion is <20%, and the image will not be affected by excessive distortion. For details of the magnification chromatic aberration diagram, see Figure 8 , it can be seen that the lens magnification chromatic aberration is less than 4μm.

[0119] In this specific embodiment, the focal length of the optical imaging lens is f=1.31 mm; the aperture value FNO=2.17; the field of view angle FOV=210.0°; and the distance TTL from the object-side surface 11 of the first lens 1 to the imaging surface 120 on the optical axis I is 51.626 mm.

[0120] In this embodiment, the image quality changes slightly under different operating temperature environments.

[0121] Table 4 Values ​​of important parameters of three embodiments of the present invention

[0122] Example 1 Example 2 Example 3 TTL / mm 54.833 54.965 51.626 f / mm 1.19 1.17 1.31 TTL / f 46.08 46.98 39.41

[0123] Although the present invention has been particularly shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims, and all such changes are within the scope of protection of the present invention.

Claims

1. An ultra-wide-angle optical imaging lens, which sequentially includes a first lens to a ninth lens along an optical axis from the object side to the image side; the first lens to the ninth lens each include an object side facing the object side and allowing imaging light to pass through and an image side facing the image side and allowing imaging light to pass through; and it is characterized in that: The first lens has a negative refractive power, the object side of the first lens is convex, and the image side of the first lens is concave; The second lens has a negative refractive power, the object side of the second lens is convex, and the image side of the second lens is concave; The third lens has a negative refractive power, the object side of the third lens is flat, and the image side of the third lens is concave; The fourth lens has a negative refractive power, the object side of the fourth lens is concave, and the image side of the fourth lens is convex; The fifth lens has a positive refractive power, the object side of the fifth lens is convex, and the image side of the fifth lens is convex; The sixth lens has a positive refractive power, the object side of the sixth lens is convex, and the image side of the sixth lens is convex; The seventh lens has a negative refractive power, the object side of the seventh lens is concave, and the image side of the seventh lens is concave; The eighth lens has a positive refractive power, the object side of the eighth lens is convex, and the image side of the eighth lens is convex; The ninth lens has a negative refractive power, the object side of the ninth lens is convex near the optical axis, and the image side of the ninth lens is concave near the optical axis; The object sides and image sides of the fourth lens to the ninth lens are all aspherical surfaces, the first lens to the third lens are all glass lenses, and the fourth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all plastic lenses; The lenses with refractive power in this ultra-wide-angle optical imaging lens are only the above-mentioned first lens to the ninth lens; This ultra-wide-angle optical imaging lens also satisfies: 1.70 < nd1 < 1.90, 35.00 < vd1 < 55.00; 1.70 < nd2 < 1.90, 35.00 < vd2 < 55.00; 1.50 < nd3 < 1.70, 55.00 < vd3 < 70.00, where nd1 - nd3 are the refractive indices of the first lens to the third lens respectively, and vd1 - vd3 are the dispersion coefficients of the first lens to the third lens respectively.

2. The ultra-wide-angle optical imaging lens according to claim 1, wherein: The fifth lens is a glass lens.

3. The ultra-wide-angle optical imaging lens according to claim 1, wherein: This ultra-wide-angle optical imaging lens also satisfies: nd2 > 1.

80.

4. The ultra-wide-angle optical imaging lens according to claim 1, wherein: This ultra-wide-angle optical imaging lens also satisfies: 1.50 < nd4 < 1.70, 20.00 < vd4 < 30.00; 1.50 < nd5 < 1.70, 55.00 < vd5 < 70.00; 1.50 < nd6 < 1.60, 50.00 < vd6 < 70.00; 1.50 < nd7 < 1.70, 20.00 < vd7 < 30.00; 1.50 < nd8 < 1.60, 50.00 < vd8 < 70.00; 1.50 < nd9 < 1.70, 19.00 < vd9 < 30.00, where nd4 - nd9 are the refractive indices of the fourth lens to the ninth lens respectively, and vd4 - vd9 are the dispersion coefficients of the fourth lens to the ninth lens respectively.

5. The ultra-wide-angle optical imaging lens according to claim 1, wherein: It further includes an aperture, and the aperture is arranged between the fifth lens and the sixth lens.

6. The ultra-wide-angle optical imaging lens according to claim 1, wherein: The ultra-wide-angle optical imaging lens further satisfies: 45.0 < TTL / f < 49.0, where TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface, and f is the focal length of the ultra-wide-angle optical imaging lens.

7. The ultra-wide-angle optical imaging lens according to claim 1, wherein: The object side surface and the image side surface of the fourth lens to the ninth lens are both high-order even aspherical surfaces.

8. The ultra-wide-angle optical imaging lens according to claim 1, wherein: The ultra-wide-angle optical imaging lens further satisfies: TTL < 55.0 mm, where TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface.

Images